nut size for 330 manifold studs

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330 4HL
Posts: 22
Joined: Wed Mar 20, 2013 1:01 pm

nut size for 330 manifold studs

Post by 330 4HL »

I'm missing a couple of the nuts for attaching the Webbers to the 330 manifold studs.
I've tried ever pitch of Whitworth, SAE, & metric.

What size & pitch are these?
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BobA
Posts: 103
Joined: Tue Nov 12, 2013 7:36 pm

Re: nut size for 330 manifold studs

Post by BobA »

Gi 330 4HL: Very nice engine detailing. If you are into diy Ferrari service, a great investment is a metric thread pitch guide. They are not expensive and will keep you from choosing the wrong nut, screw, bolt or stud. They are a series of small blades much like a feeler guage with each of the different pitches cut in the individual blades so you can see if they match a chosen fastener. I do not know the size or pitch, but suspect it is something like a 8mm 1.0 pitch. Bob
John Vardanian
Posts: 1906
Joined: Wed Sep 04, 2002 12:13 am
Location: San Francisco Area

Re: nut size for 330 manifold studs

Post by John Vardanian »

Please tell me if/when you find them. I have searched for these to no avail. If yours are like the earlier cars' the hex is 12mm, very hard to find. I located these nuts in 1.25 pitch but not 1.0.

john
PF Coupe
BobA
Posts: 103
Joined: Tue Nov 12, 2013 7:36 pm

Re: nut size for 330 manifold studs

Post by BobA »

I just measured the nuts on my 40DCL carbs and they are 8mmx1.0 with a 11mm hex. I do not see why you could not take a 1/4-20 nut and tap it to a 8x1.0. The 1/4-20 should have a 7/16 hex which is almost the same as 11mm. 7/16 = 11.1 mm
cory
Posts: 227
Joined: Thu Apr 14, 2011 7:34 pm

Re: nut size for 330 manifold studs

Post by cory »

I believe Neil at Newco products has these under his hardware section of his website.
Cory
Steve Meltzer
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Location: with Barney the Beagle boy and Enzo 8995

Re: nut size for 330 manifold studs

Post by Steve Meltzer »

I'm almost certain that these are M8 X 1.00, meaning the ID is 8mm, fine thread. These are so easy to lose that I bought a bunch, but will be the first to admit that they may not have the "correct" finish, nor am I sure of the OD, but I think it takes a 13mm wrench. (don't hold my feet to the fire on that one, unless I have my nomex Lucchese boots on). Here's a place from Amazon that has them, cheap. steve

http://www.amazon.com/Thread-Finished-M ... X+1.00+nut
steve meltzer,
"I've spent all of my money on wine, a beautiful woman, and stunning cars. Then, squandered the rest."
Steve Meltzer
Posts: 982
Joined: Mon Sep 06, 2004 10:31 am
Location: with Barney the Beagle boy and Enzo 8995

Re: nut size for 330 manifold studs

Post by Steve Meltzer »

Just back from checking the nuts that bolt the carbs to the intake on my GTC. As noted, they're M8 X 1.00 (where 1.00 is the pitch in mm). The nuts on my car are 14mm in OD, but I have some 13mm OD ones as well in my box of these. steve
steve meltzer,
"I've spent all of my money on wine, a beautiful woman, and stunning cars. Then, squandered the rest."
330 4HL
Posts: 22
Joined: Wed Mar 20, 2013 1:01 pm

Re: nut size for 330 manifold studs

Post by 330 4HL »

thanks all, I've got some shopping to do!
rick
John Vardanian
Posts: 1906
Joined: Wed Sep 04, 2002 12:13 am
Location: San Francisco Area

Re: nut size for 330 manifold studs

Post by John Vardanian »

I called Newco, he has these nuts. He is adamant that the correct nuts are not 12mm but 12.5mm in width and you need a special wrench for them. I went home and measured mine with calipers, all but one measured 11.95mm. I wonder what other 250GT owners have on their cars, 12mm or 12.5mm. Thanks.

john
PF Coupe
DWR46
Posts: 621
Joined: Tue Sep 22, 2009 8:23 pm

Re: nut size for 330 manifold studs

Post by DWR46 »

John: They are 12 mm hexes.
DWR46
Posts: 621
Joined: Tue Sep 22, 2009 8:23 pm

Re: nut size for 330 manifold studs

Post by DWR46 »

John: Need to clarify a little bit. Most cars will have 12mm hexes. However, I have seen 11mm hex on some earlier cars. These are getting pretty thin on wall thickness, so they went to 12mm for better strength. 38 DCN installations will have 11mm hex nuts.
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